1. Field of the Invention
This invention relates to a data printing device for a camera, and more particularly to a data printing device built in a camera body in which the data to be printed on the film in the camera can be viewed through the viewfinder of the camera.
2. Description of the Prior Art
It has been known in the art to provide a data printing device in a camera body to print data such as the date of the photographing. Further, it has been proposed to make the data to be printed be viewable through the viewfinder of the camera as disclosed in U.S. patent application Ser. No. 654,757 filed Feb. 3, 1976, now U.S. Pat. No. 4,085,412 filed by the instant applicant. It is desirable that the data be viewable through the viewfinder in order that the data to be printed can be confirmed.
In the camera provided with the data printing device in which the data can be viewed through the viewfinder, the optical system in the camera is markedly complicated because a diopter correction lens is needed in the optical path of the data viewing system in addition to the normal viewfinder optical system including a bright frame, a mark for zone focussing, a frame for indicating numerals for adjusting a pointer of an exposure meter and a diopter correction lens for the various marks and frames which are viewed together with the image of the object to be photographed.
Further, it has been a defect in the conventional camera with the data printing device that the numerals or characters indicating the data are liable to be blurred since a plurality of data carrying plates are superposed with each other. It is another disadvantage of the conventional camera with the data printing device that the number of parts is increased and the cost is high since the data printing device is provided with an externally operable manual switch for selectively turning on or off the light source in the device so that the data may be printed only when the photographer desires to print the data on the film.